In recent years, as a next-generation energy source, there has been proposed a fuel cell bundle constructed by electrically connecting, via a connecting member, a plurality of fuel cell stacks together, each of which is composed of a plurality of fuel cells connected to each other.
As such a fuel cell stack, there is known a fuel cell stack composed of a plurality of fuel cells electrically connected to each other via an interconnector. The fuel cell is constructed by placing a fuel electrode, a solid electrolyte, and an air electrode successively in the order named on a side surface of an electrical insulating support. Moreover, there is known a fuel cell bundle composed of a plurality of staggered fuel cell stacks, in which the adjacent fuel cell stacks are electrically connected to each other via a connecting member (refer to Patent Literature 1).